Load sense implement systems may have two or more pumps operating in parallel supplying hydraulic fluid to multiple implement functions. Typically, there may be a single load sense signal shared by these pumps. However, during portions of the operating cycle, one implement function may be operating at a high flow and low pressure while another may be operating at high pressure with high or low flow. In this scenario, the pumps deliver flow at a sufficient pressure to meet the demands of the highest pressure function. This may result in the provision of high pressure flow to a high flow but low pressure function. Separation of the pump circuits may not be desirable because, in some scenarios, flow from both pumps may be combined to meet performance requirements.
U.S. Pat. No. 4,473,090 discloses a hydraulic power system for driving implement actuators at constant speed irrespective of loads thereon or engine speed. The hydraulic power system includes a plurality of sources of hydraulic fluid under pressure for powering at least two implement control valve means. One of the pressurized fluid sources communicates with one of the implement control valve means via a restriction. In response to the pressure differential created across the restriction, a first demand valve maintains constant fluid flow to such implement control valve means by controlling communication thereof with the rest of the pressurized fluid sources. Also included is a second demand valve which maintains constant fluid flow to the other implement control valve means in response to a pressure differential across another restriction formed in a conduit communicating the first demand valve and a carry-over port of the one implement control valve means with the other implement control valve means. While beneficial, a better system is needed.